Apparatus for making gritless carboniferous printing inks



"Jan. 1, 1924 W. W. MOCK APPARATUS FOR MAKING GRITLESS CARBONIFEROUS PRINTING INKS Original Filed Feb 8.

I gvwem'cov $51 I Gum/mm Patented .llan. l, 1924.

entra n stars WALTER- W. MOCK, O'F RUTHERFORD, NEW JERSEY.

APPARATUS FOR MAKING GBITLESS CARBONIFEROUS PRINTING INKS.

Application filed February 8, 1922, Serial No. 534:,874. Renewed. November 22, 1923.

production of so-called gritless printing inks, particularly of the type known as web press or news inks, and has for its principal objects the provision of a machine which is capable of expeditiously and economically separating gritty crystalline carbon particles from carbon-containing inks and especially from such inks in which the original carbon content comprises substantial quantities of such carbon particles.

I am aware that it has been proposed to clarify varnishes and the like by the employment of so-called centrifugal clarifiers but such machines are not adapted for use without modification for the purpose of effectively separating the so-called gritty crystalline carbon particles contained in ordinary printing inks from the amorphous or non-gritty particles,owing to the fact that the specific gravities of amorphous carbon and crystalline carbon so closely approximate each other, which fact necessitates more effective control of the various features which influence the character of the resultant product than is possible in centrifugal clarifiers such as have been heretofore constructed.

My investigations have led to the discovery of a centrifuge which is ideally adapted for the treatment "of carboniferous printing inks containing very substantial quantities of carbon particles, in order to practically eliminate such gritty crystalline carbon particles therefrom and to produce an ink which is remarkably free from, gritty particles containing less than one-quarter of one per cent of such p'articles and which consequently eliminates the necessity for frequent cleaning-of the plates, as is ,now commonly "required when employing ordi:

nary carboniferous', printing inks.

Referring to the drawingsand the .con-.; struction shown therein the reference numeral 1 designates .ahollow standard in which is mounteda vertical shaft 2 having a" worm 3 adapted to be operated by a 3beltdriven gear 4 in the well-known manner. A rotary bowl 5 keyed to the upper end of said shaft projects into an enlarged chamber 11. Preferably, as shown, said bowl comprises an outer shell 6 having a removable topsection 6, substantially conforming to a cone frustrum, and having an outlet orifice 7 A supplemental bowl comprising a shell 8 and a removable bottom member 8 is supported within said outer bowl and spaced sufliciently above the bottom of the latter to afford a passage 9 for liquid which escapes through the annular outlet 10 of said supplemental bowl. The neck'll of said supplemental bowl is of sufficient size to receive an inlet conduit 12 and afford an annular overflow passage 13. Said conduit 12 is closed atits lower end and provided with a narrow slot b which sprays liquid into the supplemental bowl atan angle to the axis thereof.

A super-structurepf light construction,

for example of tin, is fittedto the hollow standard above the chamber a and the same is partitioned into an upper chamber 14, two intermediate chambers 16 and 17 and a fourthor bot-tom chamber 18. The upper chamber 14 is of suflicient height to afford an efficient working head for news ink delivered into the machine, for example in a machine having a bowl) with an outlet of 1 sq. in. area. The top of said chamber is preferably l 14% inches above the outlet orifice 7 of said bowl and its vertical wall is preferably 111} inclles high, Within the neck 15 of this chamber is fitted a strainer 19- for the removal of coarse particles. The chamber 14 is rovided with an outlet orifice 20, pref era ly adjacent the top thereof, which is adapted to dicharge into a conduit 20' the ink which backs-up into the chamber 14 whenthe inner bowl overflows due to cloggingor choking thereof by gritty particles of accumulated carbon which have been sep arated from the ink. The chamber 16 is provided with an 'outlet orifice on its outer periphery which communicates directly with and,is adapted to discharge into a conduit 21 the ink'which backs-up into the chamber 14 when the inner bowl overflows due/to clogging or choking thereof by gritty, particles of accumulated carbon which have een separated from g g As shown, these d scharge conduits 20, 21 serve to deliver such joverflow. which is obviously incompletely treated ink, j into a p e e atale fa in h ch we s the discharge issuing from orifice 7 that is discharged into conduit 22 in communication therewith. The overflowing of the ink thru said conduits 20, 21 will serve to indicate that the accumulation of carbon in the inner bowl is so large as to interfere with the proper centrifuge separation and thereby will warn the operator against further operation of the machine until the accumulated carbon has been removed.

While I have specified that preferably the top of the chamber 14 is 14% inches above the outlet orifice 7 of the outer bowl, it is obvious that the outlet orifice 20 maybe 14% inches above the outlet orifice 7 and the super-structure may extend further above the outlet orifice 20 without changing the operation of the apparatus, since the chamber 14 could not be filled above its outlet orifice. However, there would be no advantage in extending the top of the superstructure above its upper outlet orifice 20, as such an extension would be merely a waste of material without adding any increased function or capacity to the chamber 14. I do not wish to confine myself-to the exact limits of 14% inches between the orifices 7 and, 20, but for a bowl with an outlet of sq. in. area, when operating on so-called news ink, the vertical distance therebetween should not be less than 11?; inches nor more than 17 5 inches in order to obtain satisfactory results.

a The operation of the aforesaid apparatus, when ut1lizing the same for the production of gritless news ink is as follows:

News ink is prepared in the well-known manner by mixing about 10 parts of carbonblack with 90 parts'so-called printers varnish, the latter consisting essentially of lubricating oil, and then grinding the mixture in a mill. .The prepared ink is then delivered into a suitable reservoir from which it is tapped through a pipe to the chamber 14. The prepared ink delivered to the chamber 14 should be preferably maintained between about 110 to 120 F. in

order; to insure a desirable degree of v1scos1ty and prevent a minimum amount of the amorphous carbon particles from being expelled while effecting the expulsion from the mixture of crystalline carbon particles.

'The elevation of the top of the chamber 14;

above the bowl to the extent above specified, insures the maintenance of the proper pres sure that is required to regulate the flow of the mixture into the bowl so that it will I be subjected to centrifugal action therein a suficient length of time to cause the gritty particles to be thrown out of suspension and yet an insuflicient time to effect the explusion of the amorphous particles. When operatlng upon a mixture such as the foregoing,

the head of tlieliquid in the machine should be such that the rate of flow, when the machine is running 4000 R. P. M., will be between 250 and 300 gallons per hour in a machine having a bowlwith an outlet of sq. in. area.

The productdelivered through the outlet conduit 7 is remarkably free from gritty particles, notwithstanding the fact that the specific gravities of amonphous' carbon and crystalline carbon very closely approximate each other. Apparently the centrifugal machine is capable of effecting this separation of the different carbon components of the mixture, not so much because of any. difference in specific gravity between these two phases of carbon but rather because of the difi'er'ence in the specific surfares of the respective particles and in this respect is somewhat analogous to the phenomenon of the suspension of fine particles of clay in water slmultaneously with the sedimentation from the same medium of the coarser particles of clay thatare of almost identical specific gravity therewith but of quite different specific surface' In a machine of thecapacity herein described it is preferable that the area of the outlet orifice 7 of the bowl should approxi= mate sq. in., this being a dimension which will give satisfactory results when operating on carboniferous news inks in a rcentrifuge having a superstructure of the dimension described and the machine is rotating at ap-, proximately 4000 R. P. M.

Having thus described my invention, what I claim and desire to secure by U. S. Letters Patent is: I

1. lfn-a centrifugal apparatus for making gritless caroniferous printing inks, the combination comprislng a standard, a rotarysuper-structure respectively, the latter outlet conduit connecting with the interior of said I supplemental bowl and the height of such super-structure being sufficient to maintain such a head upon printing ink delivered into said supplementa such ink will remain in at least one of the bowls of said apparatus a suflicient length of time to insure the expulsion of gritty carbon particles but an insuficient time to afford,

of the expulsion ofamorphous. carbon particles from said-ink.

2. In a centrifugal apparatus for making gritless carboniferous printing inks, the combination comprising a. Standard, a rotary bowl provided with an outlet orifice, a supaforesaid bowl as to insure that,

emme pleniental bowl mounted within said rotary owl, a super-structure having a chamber of relatively large cross-section at its top and of reduced cross-section at its bottom, filtering means arranged in said bottom or-' tion of said super-structure, outlet con uits respectively connecting with the said enlarged top portion of said super-structure and with the reduced bottom portion of said super-structure respectively, the latter outlet conduit connecting with the interior of said supplemental bowl and the height of such super-structure being such that the distance between the outlet orifice of the enlarged top thereof is at least 12 inches above the outlet orifice of the outer bowl.

3. In a centrifugal apparatus for making gritless carboniferous printing inks, the

larged top portion of said super-structure and with the reduced bottom portion of said super-structure respectively, the latter outlet conduit connecting with the interior of said supplemental bowl and the height of such super-structure being such that the distance between the outlet orifice of the enlarged top thereof is at least 14: inches above the outlet orifice of the outer bowl.

4. In a centrifugal apparatus for making gritless carboniferous printing inks, the

combination comprising a standard, a rotary bowl provided with an outlet orifice, a nonrotatable super-structure extending to a substantial elevation above said bowl, an outlet orifice adjacent the top of said super-structure and an outlet orifice adjacent the bottom thereof, the height of such superstructure being such that the top outlet orifice thereof will be at least 12 inches above the outlet orifice of said outer bowl,

WALTER w. MOCK. 

